              APOD: 2017 December 21 - Solstice Sun and Milky Way

                         Astronomy Picture of the Day

    Discover the cosmos! [1] Each day a different image or photograph of our
 fascinating universe is featured, along with a brief explanation written by a
                           professional astronomer.

                               2017 December 21
                                      [2]
                          Solstice Sun and Milky Way
     Composite Image Credit & Copyright [3] : Stefan Seip [4] (TWAN [5] )

Explanation: Welcome to December's solstice [6] , first day of winter in the
north and summer for the southern hemisphere. Astronomical markers of the
seasons, solstice and equinox dates [7]  are based on the Sun's place in its
annual journey along the ecliptic, through planet Earth's sky. At this
solstice, the Sun reaches its maximum southern declination of -23.5 degrees
today at 16:28 UTC, while its right ascension coordinate on the celestial
sphere [8] is 18 hours. That puts the Sun in the constellation Sagittarius in
a direction near the center of our Milky Way galaxy. In fact, if you could see
today's Solstice Sun against faint background stars and nebulae (that's really
hard to do, especially in the daytime ...) your view might look something like
this composited panorama. To make it, images of our fair galaxy [9] were taken
under dark Namibian night skies, then stitched together in a panoramic view.
From a snapshot made on December 21, 2015, the Sun was digitally overlayed as
a brilliant star at today's northern winter solstice position, close to the
center of the Milky Way [10] .

                   Tomorrow's picture: eponymous twins [11]

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    Authors & editors: Robert Nemiroff [23] (MTU [24] ) & Jerry Bonnell [25]
                                  (UMCP [26] )
          NASA Official:  Phillip Newman Specific rights apply [27] .
              NASA Web Privacy Policy and Important Notices [28]
              A service of: ASD [29]  at NASA [30]  / GSFC [31]
                           & Michigan Tech. U. [32]
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Site notes:
  [1] archivepix.html
  [2] image/1712/WinterSolsticeMW_Seip.jpg
  [3] lib/about_apod.html#srapply
  [4] http://www.astromeeting.de/
  [5] http://www.twanight.org/
  [6] http://earthsky.org/astronomy-essentials/
everything-you-need-to-know-december-solstice
  [7] http://aa.usno.navy.mil/data/docs/EarthSeasons.php
  [8] https://en.wikipedia.org/wiki/Right_ascension
  [9] ap151107.html
  [10] https://www.nasa.gov/jpl/ charting-the-milky-way-from-the-inside-out
  [11] ap171222.html
  [12] ap171220.html
  [13] archivepix.html
  [14] lib/apsubmit2015.html
  [15] lib/aptree.html
  [16] http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  [17] calendar/allyears.html
  [18] /apod.rss
  [19] lib/edlinks.html
  [20] lib/about_apod.html
  [21] http://asterisk.apod.com/discuss_apod.php?date=171221
  [22] ap171222.html
  [23] http://www.phy.mtu.edu/faculty/Nemiroff.html
  [24] http://www.phy.mtu.edu/
  [25] http://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  [26] http://www.astro.umd.edu/
  [27] lib/about_apod.html#srapply
  [28] http://www.nasa.gov/about/highlights/HP_Privacy.html
  [29] http://astrophysics.gsfc.nasa.gov/
  [30] http://www.nasa.gov/
  [31] http://www.nasa.gov/centers/goddard/
  [32] http://www.mtu.edu/
